LLDDs should never see REQ_BLOCK_PC requests, we can handle them just
fine in the core code. There is a small behaviour change in that some
check in sr's rw_intr are bypassed, but I consider the old behaviour
a bug.
Mike found this cleanup opportunity and provdided early patches, so all
the credit goes to him, even if I redid the patches from scratch beause
that was easier than forward-porting the old patches.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>